Sunlight

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The solar energy reaching Earth's surface includes visible light,
ultraviolet and infrared radiation. Ultraviolet light is high energy
and causes damage including sunburn, fading of pigments and degradation
of compounds such as fabrics, plastic and rubber. Ultraviolet radiation
can also be used to kill harmful bacteria and parasites in water,
rendering it safe for drinking.

Infrared radiation is felt as heat, and is given off by
all objects. If your body is warmer than surrounding objects, your
body gives up more radiant heat than it receives from the surroundings,
and you will feel cool or cold. If nearby objects are warmer, such as a
heat lamp or space heater, you receive more radiant heat on that side
of your body than your body gives off, and you will feel warm on that
side. The other side may feel quite cold, however.

Much of the energy from the Sun arrives on Earth in the form of
infrared radiation. Sunlight in space at the top of Earth's atmosphere
at a power of 1366 watts/m2 is composed (by total energy) of about 50%
infrared light, 40% visible light, and 10% ultraviolet light[1]. At
ground level, this decreases to about 1120-1000 watts/m2, and consists of 44% visible light, 3% ultraviolet (with the Sun at the
zenith (directly overhead), but less at other angles), and the remainder infrared. Thus,
sunlight's composition at ground level, per square meter, with the sun
at the zenith, is about 527 watts of infrared radiation, 445 watts of
visible light, and 32 watts of ultraviolet radiation. The balance between absorbed and emitted infrared radiation has a critical effect on the Earth's climate.